37 | Keysight | E4991B Impedance Analyzer - Data Sheet
Typical Effects of Temperature Change on Permittivity
Measurement Accuracy (continued)
Typical accuracy of permittivity parameters (continued):
with temperature compensation
K1
K2
= 1 × 10-6 × (60 + 150 × ƒ)
= at 1 MHz ≤ f < 500 MHz
[r´m
1
3 × 10-6 × (1 + 10 × ƒ) ×
+10 × ƒ
×
t
2
f
1–
fo
at 500 MHz ≤ ƒ ≤ 1 GHz
[r´ m
1
3 × 10-6 × (5 + 2 × ƒ) ×
+10 × ƒ
×
t
2
f
1–
fo
K3
= at 1 MHz ≤ ƒ < 500 MHz
1
5 × 10-3 × (0.3 + 3 × ƒ) ×
[´
r m
1
+10
ƒ
×
×
t
2
f
1–
fo
at 500 MHz ≤ ƒ ≤ 1 GHz
1
5 × 10-3 × (1.5 + 0.6 × ƒ) ×
[´
r m
1
+10
ƒ
×
×
t
2
f
1–
fo
ƒ
= Measurement frequency [GHz]
13
ƒo
=
[GHz]
√
[´r'm
t
= Thickness of MUT (material under test) [mm]
[´r m = Measured value of [´r
ΔT
= Difference of measurement temperature from calibration temperature
Use ΔT = 0 °C if temperature compensation is set to off and the
difference ≤ 5 °C.
Use ΔT = 0 °C if temperature compensation is set to on and the
difference ≤ 20 °C.
ΔTmax = Maximum temperature change (°C) at test port from calibration
temperature after the calibration is performed.
Use ΔTmax = 0 °C if maximum temperature change ≤ 10 °C.